Pump



Jan. 2, 1940. .,CQRYDQN er 2,185,784

PUMP

Filed May 27, 1938. 2 shams-sheer 2 22 ad L j u@ owe` vis Another object is .to providea new and iin-holes 22.111 the borderins'edeeportion' I8 ofr the is ed Fig. 2 is a siinilargview.` upwardly to sistant material such as hard rubber. Proper.

esita-tiene 1 1 2,185,184

NITED STATES- PATENT oFrFica .v j 2,185.73? 1 I l d RullinilitilruicIvli--ovhlence R Ii The invention relates generally to pumps, and` felt-atene `endo f,the'.o'1:|e 'riinfgle, with annular more particularly to pumps of the diaphragm-instel* plahar`moiintingjsurfac-ilfl `bordering the f type adapted for pumping corrosive liquids. .clearancefchamber? `6.- j-!lgainstu .the ymounting Pumps of this character are often usedfforthef"l siliiacell oheface'offthe-.bordering.edge portion .s proportional feeding of chemicals or reagents I 8 of.thegdiaphragm'jis positioned; andisheld 5 s uch as hypochlorite; so that it is necessary" to n placebyclamping of the pump head. I2 against employ diaphragm made from rubber.'l Altfsotherfaceofthe edge portion IB.; Preferably though such diaphragme are normally reinforced,` thepiimplhead I2 ls-of a form 'similar to that frequent cracking or breakage of the prmrdIav sllc'nllii and claimed in our aforesaid application,

m phragms has been experienced, v andis secured in clamping relation to the border- 10 The primary object ofthe present inventloniatjfi'ng` edge I8 l`of thev diaphragm by similar means, therefore, to construct a diaphragm pump ofthisf fthismeans .including rigid clamping plate means character wherein such cracking, breaking. or I9 ,and clampingscrews 20 extending through wear on the diaphragm is materially reduced.` borderingvporti'ons l.2l of .the head I 2, through proved pump diaphragm constructed tnn'iiniliiize.e4 diaphragm and screwed into 'the rigid .frame wear on the diaphragm. member Il. l Other objects and advantageswill-become apevv v'Io cooperate with-the 'diaphragm I lin formparent from the followingdescriptiomtaken in ing a pump chamber, thepump head I2 has a ze connection withthe accompanying.drawings', in recess 23 formed therein whichppposes that porwhich: e l." i -tion of the diaphragm which lies inwardly of the Fig. 1 isahorizontal plan viewftakenthrough a* clamped border. portion I8 thereof. Since thediaphragm pump embodying ith@ .features of the chamber-23 is to be exposed to corrosive fluids. invention. f the pump' head I2 is formed from a. corrosion reshow the outlet opening ofthe pump chamber clamping-0f the diphregm I3 is assured by fImand showing the diaphragniina diiferent posii118 the Pump head i2 S0 that its reCeSS 23.18 tion. i bordered Abyan annular surface 24, lying general# Fig. 3 is n view simiiarltojrigi 2 showing the lv 1na plane parallel tothe opposed surface I1 in diaphragm advanced toward the left'beyond the of the mounting member Il, there being a pro, 3@

positions of Figs. I and 2. e .lettingL annular bead or ridge 25 on said surface F194 is a perspective view oftheY diaphragm. 24 ,whichv is pressed into the diaphragml to pro- For purposes of disclosure, 'we have illustrated duce 'a more perfect sealing action. The pump in the drawings and will hereinafter describe in ohember 23,l 0f Course, has an inlet Opening 23 its detail the preferredembodiment of the invention, (Fig- 1) and en Outlet Opening 21 (Fi'E- 2) which,` 35 with the understanding that we do not intend to are controlled by suitable valves, (not shown) limit our invention to the particular construction.l Sueh. fOr example, aS those Shown and' Claimed and arrangement shown, `it being contemplated in Our aforesaid applieaiionthat various changes may be made by those The actuating I'Od i4. eSvhei'eiIl ShOWn'. iS.con skilled in` the art vwithout departing from the nected to the diaphragm I3 so es to be detach 4,0 Spirit and scope of the appended claims, able therefrom for the purpose of replacing the In the formchosen for'disclosure herein the diaphragm. For this purpose a metallic. push invention is embodied in a pump lo of thej genplate 301s secured. as by e rivetedv connection 3|, eral-character described and claimed in vour coto the end of the rod Il and within the pump er; pending spplieation,serin1 Number 25,467,n1ed chamber 23 e clamping plate 32 is provided4 4s .inne '1, 1935, now Patent No. 2,145,566, dated lwhereby the center of the diaphragm may be January 31, 1939. As herein shown the pumpyin clamped against the push plete 30. ,The clampcomprises a main base or frame member II upon ing plate 32 as herein shown comprisesa central which a pump body or head I2, a pump diametallic ring 33 from which a plurality-of fixed .no phragm I3 and a diaphragm-actuating rod Il studs 34 project. The ring 33 has -a protective 5o are operatively mounted and associated. covering 35 of hard rubber or the like molded The frame member II is preferably formed thereon; and the studs 34 project through holes from a rigid casting to provide an operating open- 36 (Fig. 4) in the diaphragm, and through coring i5 through which the actuating rod I4 exresponding holes in the push plate 30. Nuts 31 tends, there being a recess or clearance chamber Aon the studs Il act to clamp the center of the action, the degree or amounts of its contact with ridge 88 is provided on the covering 35 outside of the studs 34 so as to efi'ectually seal and protect 'the studs against the corrosive iiuid in the pump chamber 23. A

Since the diaphragm I3 ls subjected to the action of corrosive liquids, it is formed from a corrosion resistant flexible material such as soft rubber; and because of the pressures to which it is subjected the diaphragm I3 is reinforced as by means of a sheet 40 of fabric moulded in the rubber of the diaphragm. In accordance with the present invention the diaphragm and the associated parts of the pump are so formed as to avoid excessive wearing stresses on the diaphragm; and articularly so as to avoid stresses on reinforcing fabric which might tend to break the fabric, and to avoid tearing, cutting or breaking of the rubber of the diaphragm whereby to insure continued protection of the fabric from the corrosive liquid.

To this end the reinforcing fabric 40 is located midway between the two side faces or surfaces of the diaphragm I3, and the diaphragm is performed or molded to provide an annular ridge or bead 6I of arcuate cross section located be-A tween the clamped central area 42 and the clamped bordering edge I8.

When mounted in its operating position, the diaphragm i3 is preferably located so that the bead I projects into clearance space I8 between the push plate 3B and the side wall of the space I6. Thus when the push plate is advanced to the forward position of Fig. 3, there is no material stretching of the diaphragm I3 in a radial direction; and particularly there is no radial stretching of the diaphragm in the central region occupied by the reinforcing fabric 4U. In such advancing movement of the push plate 30, the rubber of the diaphragm I3 is stretched slightly on the left hand face of the diaphragm, and is slightly compressed on the right hand face, but in the median zone of the fabric di) no tearing or stretching forces are exerted.

Similarly, when the actuating rod I 4 is withdrawn, no material stretching forces are applied to the fabric 40, and the zones of compression and stretching of the rubber of the diaphragm are reversed.

To prevent tearing or undue wear on the diaphragm in 4such actuation thereof, the various clamping elements acting on the diaphragm I3 are formed with rounded edges and supporting surfaces to engage the diaphragm wherever relative movement and contact takes place between such elements and the diaphragm. Thus the push plate 30 has a receding border flange 5I) with a rounded annular face 5I against which the outer surface of the bead 4I may engage with a rolling action as the push plate is advanced from the position of Fig. 2, through the position of Fig. 1 and to the most advanced position of Fig. 3. In such advancingr movement the other face of the bead 4I, adjacent the outer border portion I8, increases, with a rolling the bordering face 2d of the pump head I2.

In movement of the diaphragm in the other direction from the position of Fig. 3, through the position of Fig. 1 and to the position of Fig. 2, the outer or right hand face of the bead 4I progressively, and with what might be termed a rolling action, engages an annular rounded edge surface 54 formed between the side wall vbe noted that in its of the recess I 8 and the clamping surface I7 of the frame member II. On the opposite or left hand face of the diaphragm, such retraction of the diaphragm causes rolling or progressive engagement of the diaphragm surface with an annular rounded surface 55 formed on the clamping face of the covering 35.

The preformed pump diaphragm of the present invention is, of course, proportioned so that in the maximum pump stroke for which it is intended. there will still remain an appreciable curved formation in the cross sectional view of the diaphragm. as will be evident inFigs. 2 and 3. 'Ihus radial tension or stretching forces are avoided in the fabric reinforcing, whereby to increase materially the service life of the diaphragm. Moreover, the rolling or progressive engagement of the various associated or clamping parts with the faces of the diaphragm insures long wear, and prevents tearing, cutting or premature cracking of these faces. It will pumping or exhaust stroke the diaphragm has a material portion of its area backed up by the flange 5U of the push plate, whereby to reduce the stress in the diaphragm I3 and thereby lengthen its useful life. 'I'his beneiicial action of the push plate is particularly valuable where the pump is being used to inject the fluid against a high line pressure. Moreover, the contact of the diaphragm with the push -plate during the pumping stroke results in a smaller free or unbacked area in the diaphragm, and because of this it has been found that the present construction produces more uniform delivery volume than has heretofore been obtainable with diaphragm pumps.

In its flexing from one position to another, it will be noted that the diaphragm of the present pump, regardless of the direction f shifting movement of the actuating rod I has a portion which is preformed to a generally frusto-conical form so that in cross section it lies at an acute angle to the axis of the rod I4; and that in such movement this frusto-conical portion is moved toward a right angular relation to said axis. Thus we may consider that portion of the bead di lying between the border I8 and the highest portion oi' the bead as such afrusto-conical portion, as shown in Fig. 1,' and when the rod I4 is advanced to the position of Fig. 3, this frusta-conical portion is moved toward a right angular relation to the axis of the rod I4. In such movement there is no stretching of this frusto-conical portion, and this action contributes to the,long life of the diaphragm of the present pump.

The inner half of the bead 4| maybe coni sidered as having a similar action when the diaphragm is iiexed in the opposite direction from its normally preformed shape to the position of Fig. 2: and while the present pre-formed diaphragm provides for such non-wearing, nonstretching exure in either direction from its normal preformed shape, it will be evident that by coordinating the pump stroke with form of the diaphragm, one of these generally frustoconical portions might suffice to attain in a measure the advantages and long life of the present construction.

We claim as our invention:

1. A pump of the character described comprising a rigid frame element having an annular clamping face, a flexible rubber diaphragm, a pump head recessed to cooperate with said diaphragm in forming a pump chamber, said head and said frame element being clamped upon the borderof said diaphragm, and an actuating rod secured to a predetermined area ofthe .central portion of said diaphragm for flexing the diaphragm, said diaphragm being molded with an' annular bead of arcuate cross section disposed inwardly of its clamped border, said annular bead being of a width extending lfrom the clamped border to said predetermined area.

2. A pump of the character disclosed comprising in combination, a mounting element having an opening and a borderingclamping face', a pump head having a recess bordered by a clamping face, a flexible rubber diaphragm having its border clamped between said clamping faces, an actuating rod extending through said oi said annular bead during the discharge strokeo! the pump.

JEFF CORYDON.

u RUDY Lowa. 

